Cylinder lock



li 'atented Oct. 3]., 1922.

KMMTEO STATEfi NORMAN B. HURID, OF NEW BRITAIN, CONNECTICUT, ASSIGNOR TO AMERICAN HARDWARE CORPORATION, OF NEWBRITAII'T, CONNECTICUT. COBTE'ORATION OF CONNECTICUT.

CYLINDER noon.

Application filed April 25, 1922. Serial No. 556,454.

To alt whom it may concern/.- 7

Be it known that 1, NORMAN B. HURD, a citizen of the United States of. America, residing at New Britain, Hartford County, Connecticut, have invented a new and useful Cylinder Look, of which the following is a specification.

My invention relates to in'iprovements in locks of the so-called pin cylinder type. Among the objects of the invention are the following: the provision of simple and effective means for preventing the accidental or unintentional operation of the look under certain conditions and the provision of means to prevent oil from working into the pin tumbler chambers in the event the lock is employed in places where such a thing would be likely to occur. In locks of this character it is desirable to keep the pin tumblers free from oil, which tends to gum and interfere with the free operation of the same. Inasmuch as such locks are now frequently used in connection with parts of automobiles, where oil and grease abound, it is manifest that this feature of my invention is of great utility.

In the accompanying drawings:

Fig. 1 is a longitudinal section of my invention.

Fig. 2 is a cross section on the line 22 of Fig. 1.

Fig. 3 is a detail View of the under side of the key barrel and cam.

1 represents the usual body of the pin cylinder lock. 2 represents a key barrel which passes through the body and is rotatable therein by means of a suitable so-called fiat key, indicated in dotted outline in Fig. 1. 3 represents a roll-back or eccentric at the inner end of the key barrel, for imparting motion to some other part, not shown, when the key barrel is rotated. 4-4: represent the usual. pin, tumblers which, excepting when a proper key is used, serve to prevent the key barrel from rotating relatively to the body 1.

The key slot in the key barrel of a pin tumbler lock usually formed by a tool which slots the underside of the key barrel from end to end. Hence, when the key barrel is in place, it obvious that there is an open slot extending entirely through the barrel from the front to the rear through which oil may freely travel, in the absence of effective means to prevent the same. Since the lock may be placed in such a position that its inner end is in the vicinity of an ex cess of oil, I provide simploand effective means to check the passage of oil through the key slot. or the like, indicated at 5, whichis forced into a suitable opening extending transversely through, or partially through, thekey barrel, as shown in Figs. 1 and 2. This pin acts as a wall located just beyond the pin tumblers and beyond the extreme end of the key when the latter. is fully in place, as shown in Fig. 1.

6-6 are annular grooves extending circumferentially around the key barrel close to the rear end of the body or casing 1. These likewise have the effect of retarding the passage of oil from the inner end of the key barrel toward the front thereof.

As shown, the end of the pin 5 is countersunk or recessed to receive a detent 7, which is located in the recess in the casing 1 and which is impelled by a spring 8 toward the key barrel, so that it will drop into the recessed end of the pin 5 when the key barrel stands in one position. By this simple means the key barrel is frictio-nally held against being accidentally or .unintentionally turned, and the detent may be positioned within the casing whereever desired around the key barrel. In the form shownthe spring pressed detent 7 is located in a position to frictionally hold the key barrel against turning when the key is inserted and thepins are positioned properly to release the key barrel. It frequently happens that a user desires to insert his key in the lock and leave it there for a certain period. Manifestly, with the key in the lock, the key barrel might be unintentionally jarred out of position but the effect of the detent is to prevent this excepting as power is actually applied to the key for that pur pose. I have not shown the detent'located in any other position but, as I have indirated it may be located wherever desired around the key barrel. In that form of my invention. shown herein it will be noted that the pin 5 performs the double function of stop to check the passage of oil, and key barrel retaining member. v i i I am aware that various modifications may be made without departing from the scope of the invention.

What I claim is 1. In a pin cylinder look, a key barrel having a key slot extending longitudinally This means comprises a pin therethrough, in tumblers, and means extending aeross said slot beyond the tumblers and intern'iediate the lengthof the key plu for closing the slot.

2. In a .pin cylinder look, a key barrel having a key slot extending longitudinally theretlnrough, pin tumblers and means e20 and means co-acting with the recessed portion of'the plug for yieldingly holding the key barrel against rotation;

4;. In a pin cylinder look, a key barrel having a key slot extending longitudinally therethrough, pin tumblers, means extendlng across said slot beyond the tumblers and intermediate the length of the key plug,

for closing the slot,- said means comprising a plug, and means co-acting with one end of said plug to yieldingly hold the key barrel against rotation.

5. In a pin cylinder look, a key barrel having a keyslot extending longitudinally therethrough, pin tumblers coacting with said key barrel, an annular groove around the key barrel near the inner end to check the creeping of oil from the rear towards the frontof the lock. Y

6; In a pin cylinder look, a key barrel having a key slotextending longitudinally therethrough, pin tumblers coacti'ng with Said key barrel, a plurality of annular grooves around the key barrel near the inner end to check the creeping of oil from the rear towards the front of'the lock.

NORMAN B. HURDj 

